Bi-mode Dielectric Logging Tool Antenna Configuration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Dielectric logging tools are limited in their ability to collect data in multiple orientations, which is necessary due to the varying composition and properties of formations, as they typically operate in either broadside or endfire modes, lacking versatility in lossy environments with low resistivity.
Innovation Solution
A dielectric logging tool with a transmitter/receiver configuration capable of operating in both broadside and endfire modes, utilizing a septum and housing design that allows for the separation and combination of electromagnetic signals to adapt orientation, enabling efficient data collection in multiple directions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a dielectric tool operates in broadside mode with antenna perpendicular to tool axis, then coupling gain is improved, but depth of investigation is reduced and it is more affected by standoff
Solution Approach 1:
The dielectric tool is designed with antennas that can operate in multiple modes (broadside and endfire) by changing the excitation configuration. The same physical antenna structure serves dual purposes: when excited in one configuration it provides high coupling gain for low-resistivity formations, and when excited in another configuration it provides greater depth of investigation. This multi-functionality resolves the contradiction by allowing the tool to adapt its characteristics based on formation conditions.
2Length of moving object
If a dielectric tool operates in endfire mode with antenna parallel to tool axis, then depth of investigation is improved, but coupling gain is reduced and it is more affected by lossy environments
Solution Approach 1:
The dielectric tool employs a universal antenna system that can be excited in different modes to serve different measurement needs. The same antenna structure provides both endfire mode operation for deep investigation in high-resistivity formations and broadside mode operation for shallow investigation in low-resistivity formations. This resolves the contradiction by making the tool adaptable rather than fixed in its characteristics.
3Device complexity
If a dielectric tool uses fixed antenna orientation, then device complexity is reduced, but adaptability to different formation conditions is limited
Solution Approach 1:
The patent implements a universal antenna system where the same physical antenna structure can operate in multiple modes (broadside and endfire) by changing the excitation configuration rather than requiring separate antenna structures. This achieves adaptability to different formation conditions without proportionally increasing device complexity, as the multi-functionality is achieved through control system flexibility rather than hardware proliferation.
Solution Approach 2:
The dielectric tool employs dynamic switching between different operational modes by changing the excitation configuration of the antennas. Rather than being fixed in a single orientation or mode, the system can dynamically adapt its electromagnetic field configuration to match the specific formation conditions being investigated, allowing optimal performance across varying geological conditions.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables more comprehensive and accurate formation property determination by allowing operation in multiple modes, improving depth of investigation and reducing the impact of standoff and mudcake effects, thereby enhancing data collection in diverse geological conditions.
Implementation Method 1
an electromagnetic signal is generated at the transmitter. The electromagnetic signal propagates through the formation such that a portion of the electromagnetic signal reaches the receiver
Implementation Method 2
A dielectric logging tool with a transmitter/receiver configuration capable of operating in both broadside and endfire modes, utilizing a septum and housing design that allows for the separation and combination of electromagnetic signals to adapt orientation
Data Source
AI summary
A transmitter/receiver for use in a dielectric logging tool. The transmitter/receiver generally includes a housing, a septum, a first antenna, and a second antenna. When operated as a transmitter, a first and second electromagnetic signal are emitted by the first and second antenna, respectively. The housing and septum are shaped to combine the first and second electromagnetic signals into a combined signal having varying orientations depending on the phase difference between the first and second electromagnetic signals. When operated as a receiver, an incoming electromagnetic signal is divided into a first and second component signal. The first and second component signals are directed to the first and second antennas, respectively, where they are converted into first and second electrical signals. The first and second electrical signals can then be combined, by adding or subtracting the signals for example, to produce a resultant electrical signal corresponding to incoming electromagnetic signals having different orientations.